The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing are needed. In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometric size (i.e., the smallest component that can be created using a fabrication process) has decreased.
One type of capacitor is a metal-insulator-metal (MIM) capacitor, which is used in mixed signal devices and logic devices, such as embedded memories and radio frequency devices. Metal-insulator-metal capacitors are used to store a charge in a variety of semiconductor devices. Although existing processes for manufacturing metal-insulator-metal capacitors have generally been adequate for their intended purposes, as device scaling-down continues, they have not been entirely satisfactory in all respects.